I haven't flown in about 6 years, before the restrictions on carry-on liquids. I always put my toiletries in my carry-on since I'm pretty particular about my hair products. I found some small plastic bottles in the travel toiletry section at Walmart and they're perfect for my shampoo and conditioner. They're small enough to fit 3.4 oz to comply with the TSA restrictions, but do the bottles have to have the total oz. written on them, similar to the way glass measuring cups do? Or does security just go by the size of the bottle, not what's written on it?